Method Call

pkg/filter/ql/function.go:160–286

(args []interface{})

type Foreach struct{}

func (f *Foreach) Call(args []interface{}) (interface{}, bool) {
	if len(args) < 3 {
		return false, false
	}

	s := args[0] // iterable (slice or map)
	if s == nil {
		return false, false
	}

	v, ok := args[1].(*BareBoundVariableLiteral) // item (variable)
	if !ok {
		return false, false
	}

	e := args[2] // predicate (expression)
	if e == nil {
		return false, false
	}

	var valuer = MapValuer{}
	if len(args) > 3 { // optional predicate captures
		for i := 3; i < len(args); i++ {
			m, ok := args[i].(MapValuer)
			if !ok {
				continue
			}
			maps.Copy(valuer, m)
		}
	}

	segments := make([]*BoundSegmentLiteral, 0)

	// obtain bound segments used in expression
	var useCallValuer bool
	walk := func(n Node) {
		switch exp := n.(type) {
		case *BoundSegmentLiteral:
			segments = append(segments, exp)
		case *Function:
			useCallValuer = true
		}
	}

	switch expr := e.(type) {
	case *BinaryExpr:
		WalkFunc(expr, walk)
	case *NotExpr:
		WalkFunc(expr, walk)
	}

	switch elems := s.(type) {
	case []string:
		for _, elem := range elems {
			if f.evalExpr(e, useCallValuer, f.stringMapValuer(v, elem), valuer) {
				return true, true
			}
		}